You can buy these software programs at your local computer store or download them from one of many online stores.
Here are some recommendations on the most popular paid antivirus programs:
- Grisoft's AVG software. This is the program that I use on my computers at home. I like it because it's unobtrusive, does a good job and doesn't seem to impact the speed of my computer. I buy the Anti-Virus version, because I don't need a internet nanny, I just need to block the most common, hidden threats.
- Avast: Haven't used this one, but it gets good reviews on several PC websites I visit.
- Symantec's End Point Protection: We use at work, and it seems to work fairly well. I'm not a big fan of Symantec because their tech support is a nightmare, but the product works as it should. Be aware that you have to buy a least 5 licenses at a time, so this product is better for small to medium businesses.
- Avira: I have not used this program personally. However, the Avira software got a great review from my favorite computer magazine, PC World, so that’s good enough for me.
- G-Data: This is a newer product, so I don't know much about it, except that it gets really good marks on the review websites.
This PC World article has some more recommendations, and here's another antivirus software article on PC Mag.
If you can't afford to buy antivirus protection, you can always download any of the free versions I mention on my free virus protection page.